package j05jiekou;

public interface I1 {
    //接口就是规范
    public abstract void f1();
}

class C1 implements I1{
    public void f1(){
        System.out.println("i am f1");
    }
}

abstract class C2 implements I1{

}
class C22 extends C2{
    @Override
    public void f1() {
        System.out.println("f1 in c22");
    }
}

class C1Test{
    public static void main(String[] args) {
        new C1().f1();
        new C22().f1();
    }
}
